1. Field of the Invention
This invention relates to a technology for specifying an area which matches a predetermined condition from an image obtained by imaging a depressed part of a specimen holding plate and obtaining a density value of this area.
2. Description of the Related Art
In medical and bioscience experiments, a fluid (e.g. a culture fluid), culture media and the like are, for example, poured into depressed parts called wells of a plate-like device on which a multitude of wells are arrayed and cells or the like cultured here are observed. Such a device is called, for example, a microplate or a microtiter plate. For example, in the process of developing an anticancer drug, a multitude of samples obtained by causing various drugs to act on cells at different densities are observed and the life and death of the cells are judged. Various optical devices for supporting such observations have been conventionally proposed.
For example, in an optical apparatus disclosed in the description of U.S. Pat. No. 7,718,131, wells are imaged by irradiating light from above the wells and receiving light transmitted to a lower side. In this technology, an image of one well is reformed from a plurality of partial images imaged while light is irradiated in different manners to cope with a problem that the shadow of a side wall surface of the well is reflected on an image due to the incidence of light focused by a lens.
Even by an imaging method taking into account the influence of the wall surface of the depressed part as in the above conventional technology, it is difficult to completely eliminate this influence. Particularly, a method for accurately calculating a numerical value having the influence of a wall surface eliminated therefrom when it is tried to quantitatively calculate the image density of a specific area in an image has not yet been established.